JPH04294647A - Optical amplifier relay transmitter - Google Patents

Abstract

PURPOSE:To attain the maintenance management for kinds of a fault and a caused position or the like in the multi-relay transmission by optical amplification. CONSTITUTION:An optical transmission section 1 of an optical transmitter 4 generates information to be sent as a main signal, a sub transmission section 2 generates a sub signal for maintenance management and an optical synthesis section 3 sends a transmission signal subjected to wavelength multiplex. A repeater 9 terminates only the sub signal, the main signal is amplified by an optical amplifier section 7 and the result is sent and relayed as an optical signal. An optical demultiplexer section 6 of an optical receiver 11 demultiplexes the multiplexed optical signal into the main signal and the sub signal, the sub signal is terminated by a sub reception section 8 and the main signal is decoded by an optical reception section 10. Thus, a fault type, its cause and its caused position are discriminated by checking the sub signal.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical amplification repeater transmission device for transmitting information using optical signals.

0002

2. Description of the Related Art FIG. 3 is a block diagram showing a relay transmission system using optical amplification, as shown in, for example, the 1990 Institute of Electronics, Information and Communication Engineers Autumn National Conference Proceedings B-765.
1 is an optical transmission section that converts information into an optical signal and transmits it; 5 is an optical fiber that is a transmission medium for the optical signal; 7 is an optical amplification section that amplifies the attenuated optical signal as it is; 10 is the transmitted light This is an optical receiver that receives signals.

Next, the operation will be explained. Information to be transmitted is converted into an optical signal by the optical transmitter 1 and transmitted through the optical fiber 5. The optical signal attenuated due to loss in the optical fiber 5 is amplified as an optical signal by the optical amplifying section 7. The optical signal transmitted by the optical fiber 5 and relayed by the optical amplifying section 7 is received by the optical receiving section 10 and the information is restored.

0004

[Problems to be Solved by the Invention] Since the conventional optical amplification repeater transmission equipment is configured as described above, when multi-reply transmission is carried out, it is difficult to identify the location and cause of failures such as optical fiber breaks or failures in the optical amplification unit. There were problems such as the inability to identify and difficulty in maintenance and management.

[0005] This invention was made in order to solve the above-mentioned problems, and it is possible to identify the location and cause of the failure, and perform maintenance and maintenance.
The purpose is to obtain a device that is easy to manage.

[0006]

[Means for Solving the Problems] An optical amplification repeater transmission device according to the present invention is configured to transmit sub-signals for maintenance and management through the same optical fiber as the main signal. In other words, an optical transmitter converts the main signal into an optical signal and transmits it, a sub-transmitter converts the sub signal into an optical signal with a different wavelength from the main signal and transmits it, and combines the optical signals with these two wavelengths. an optical transmitting device consisting of an optical multiplexing section that separates the combined optical signal, an optical demultiplexing section that separates the combined optical signal, a sub-receiving section that receives the separated sub-signal, and amplifies the separated main signal as an optical signal. A relay device consisting of an optical amplification section, a sub-transmission section that converts the sub-signal into an optical signal with a wavelength different from that of the main signal and transmits it, and an optical multiplexing section that combines the optical signals of these two wavelengths, and Equipped with an optical receiver consisting of an optical demultiplexer that separates optical signals, an optical receiver that receives the separated main signal, and a sub-receiver that receives the separated sub-signals, the main signal and sub-signal are the same. This is an optical amplification repeater transmission device that performs wavelength division multiplexing transmission using an optical fiber, optically amplifies the main signal in a repeater, and terminates only the sub signal.

[0007]

[Operation] In the present invention, it is possible to specify the location and cause of a fault and to notify fault information by using a sub-signal for maintenance and management that is wavelength-multiplexed with the main signal.

[0008]

[Example] Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is an optical transmitter that converts information into an optical signal and transmits it, and 2 is an optical transmitter that converts a sub-signal for maintenance and management into an optical signal with a different wavelength from that of the optical transmitter 1 and transmits it. 3 is an optical multiplexing unit that combines the optical signals of these two wavelengths; 4 is the optical transmitting unit 1, the sub transmitting unit 2;
An optical transmitting device consisting of an optical multiplexer 3, 5 an optical fiber which is a transmission medium for optical signals, 6 an optical demultiplexer that separates wavelength-multiplexed main signals and sub-signals, and 7 a separated main signal. An optical amplifying section that amplifies the optical signal as it is; 8 an optical receiving section that receives the separated sub-signal; 9 an optical demultiplexing section 6; an optical amplifying section 7;
, a relay device consisting of a sub-receiving section 8, an optical transmitting section 2, and an optical multiplexing section 3; 10 is an optical receiving section that receives the main signal separated by the optical demultiplexing section 6; 11 is the optical demultiplexing section 6; , a sub-receiving section 8, and an optical receiving section 10.

Next, the operation will be explained. The information to be transmitted is converted into an optical signal by the optical transmitter 1, and maintenance and
The sub-signal for management is converted by the sub-transmission section 2 into an optical signal having a wavelength different from that of the main signal. For example, by making it possible to transmit information such as the type of fault that has occurred and the section in which it has occurred using the sub-signal, and adding a parity check bit to monitor the transmission quality in each relay section, it is possible to prevent optical fiber disconnections and It becomes possible to detect failures such as amplification unit failures and deterioration of transmission quality, and to transfer information such as the type of detected failure and the section in which it occurred. The converted optical signals of two different wavelengths are combined by the optical multiplexer 3 and transmitted through the optical fiber 5.

The optical signal attenuated due to loss in the optical fiber 5 is amplified and relayed by a repeater 9. In the relay device 9, the wavelength-multiplexed optical signal is separated into a main signal and a sub-signal by the optical demultiplexer 6, and the sub-signal for maintenance and management is terminated by the sub-receiver 8. The sub-signal is terminated and a parity check of the sub-signal in this relay section is performed to detect deterioration in transmission quality and to detect failures such as optical fiber breaks. Optical demultiplexer 6
The main signal separated by is amplified as an optical signal by an optical amplifying section 7. The sub transmitter 2 maintains and manages the next relay section and converts the sub signal containing information on the type and location of the fault detected in the previous relay section into an optical signal with a wavelength different from that of the main signal. The signals are converted, combined by an optical multiplexer 3, and transmitted through an optical fiber 5.

Transmission through the optical fiber 5 and relaying through the repeater 9 are repeated, and the wavelength-multiplexed main signal and sub-signal are separated by the optical demultiplexer 6 in the optical receiver 11, and the sub-signal is separated by the optical receiver 8. , the main signal is terminated at the optical receiver 10 and the information is restored. In particular, at the end of the sub-signal in the optical receiver 11, the type of failure detected in each relay section intermittent relayed from the optical transmitter 4 by the relay device 9 and the position information of the detected relay section are obtained.

FIG. 2 is a diagram showing an example of the format of the sub signal. In the figure, F is the frame synchronization pattern of the sub signal, and the contents of the sub signal for the first to nth relay sections are continuous, and the parity bit (P
TY) follows. REC is a signal indicating that sub signal reception is interrupted, SO
UT is a signal indicating main signal optical amplifier output drop, LDCUR
R is a signal indicating an abnormality in the main signal optical amplification element, and AIS is a signal indicating an alarm display. The sub-receiving section 8 sets the contents of the sub-signal for the relay section to which it belongs, and sends it to the sub-transmitting section 2. REC is used when no sub-signal is received from a section upstream from the relay section to which it belongs. SOUT is set when the output of its own optical amplifier does not meet a predetermined criterion. Similarly, LDCURR is set when the own optical amplification element shows an abnormality. Further, AIS is set when an error has already occurred in the upstream section and there is no abnormality in the own section. Note that the number of bits and encoding method of each of these signals are arbitrary. Furthermore, the number and types of signals are not limited and are arbitrary.

Example 2. In the above embodiment, the case of two-wave multiplexing of the main signal and the sub-signal is shown, but a larger number of main signals may be wavelength-multiplexed.

Example 3. Furthermore, although the above embodiments have been shown in the case of unidirectional transmission, bidirectional wavelength multiplexing may also be used.

[0015] As a technique similar to the present invention, there is a technique disclosed in Japanese Patent Application Laid-Open No. 83899/1983. This technology is known as an "optical fiber transmission path fault detection method".
This invention discloses a method for searching for a failure in a transmission path when an optical cable is connected from an input station to an output station via a cable connection device or relay device. More specifically, a method is adopted in which the optical signal input from the optical cable is temporarily converted into electricity at the relay device, and then converted into electricity again. This is an attempt to identify the location of the disconnection by generating a signal at a frequency of (corresponding to the sub-signal of the present invention) and transmitting this one after another to the next cable connection device or relay device. In contrast, in the present invention, the repeater amplifies and repeats the main signal input from the optical fiber as an optical signal, and the sub-signal is different from a simple frequency signal and is not only subject to disconnection. It is also possible to judge the quality of the transmission path, failure of the amplifier, etc.

[0016]

[Effect of the invention] As described above, according to this invention, maintenance and
Since the sub-signal for management is wavelength-multiplexed and transmitted through the same optical fiber as the main signal, it is possible to identify the location and cause of failures such as optical fiber breaks and equipment failures even in the case of multi-reply transmission, making maintenance easier.・It has the effect of making management easier.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an optical amplification repeater transmission device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a format of a sub-signal according to the present invention.

FIG. 3 is a block diagram showing a conventional optical amplification repeater transmission device.

[Explanation of symbols]

1 Optical transmitter 2 Sub transmitter 3 Optical multiplexing section 4 Optical transmitter 5 Optical fiber 6 Optical demultiplexing section 7 Optical amplification section 8 Sub-receiving section 9 Relay device 10 Optical receiver 11 Optical receiver

Claims (1)

[Claims] Claim 1: An optical amplification repeater transmission device having the following elements: (a) an optical transmitter that converts a main signal into an optical signal and transmits the converted signal; and an optical transmitter that converts a main signal into an optical signal and transmits it, and a sub-signal for maintenance and management that is a different optical signal from the main signal. (b) an optical transmission device having a sub-transmission unit that converts the optical signal into a sub-transmission unit for transmission, and an optical multiplexing unit that combines these two optical signals, (b) an optical demultiplexing unit that separates the combined optical signal, and a separated sub-signal; an optical amplifying section that amplifies the separated main signal as an optical signal, and a sub transmitting section that converts the sub signal into an optical signal different from the main signal and transmits it. (c) a repeater having an optical multiplexing section for combining signals; (c) an optical demultiplexing section for separating the combined optical signals; an optical receiving section for receiving the separated main signal; and an optical receiving section for receiving the separated sub-signal. (d) an optical fiber that is located between the optical transmitter, the relay device, and the optical receiver and transmits optical signals;